1. Field of the Invention
This invention relates to improvements in hand-held, electric motor driven so called "all purpose" reciprocating saws, such improvements being: (1) the dampening mechanism to dampen the vibration due to the aggressive orbital cutting action of the saw blade; and (2) the heat sink action of such dampening mechanism.
2. Description of the Prior Art
Hand-held electric motor driven "all purpose" reciprocating saws in which the cutting blade is reciprocated in a path substantially parallel to the axis of rotation of the electric motor and in which the blade may be reciprocated in a pure reciprocating or substantially straight axial path or in an aggressive orbital path are disclosed for example in U.S. Pat. No. 3,461,732 and in the copending application of Alan J. Ritz entitled "Control for the Orbital Action of a Reciprocating Power Saw".
A patentability search on the feature of using a selected lag angle between the eccentrically controlled carrier guide and wobble drive mechanism for reciprocating the saw blade carrier in the carrier guide, and proportioning the relative weights and distances of travel of such carrier guide and such saw blade carrier to effect a near perfect balance and a dampening of vibration transmitted to the user uncovered only the following U.S. Pat. Nos.:
______________________________________ 1,648,008 3,205,722 2,501,631 3,404,574 2,917,088 3,461,732 2,931,402 3,729,823 3,205,721 ______________________________________
None of these patents disclosed the feature of cooperating the relative reciprocal movements and relative weights of the carrier guide and blade carrier (including the saw blade) to effect either the dampening of vibration and the use of the carrier guide to also provide a heat sink.